Postoperative Agitation After Hip Fracture Surgery
A 78-year-old man is postoperative day 1 after intramedullary nailing of a right hip fracture. He was independent, drove, and managed his own finances before admission. He has hypertension and mild memory complaints but no prior dementia diagnosis. Overnight he becomes agitated, tries to climb out of bed, pulls at his IV and urinary catheter, and does not recognize his daughter. He is oriented to person only; attention fluctuates. Temperature 37.9°C, HR 104, BP 138/76, SpO2 94% on room air, respiratory rate 22. Medications: morphine PCA, ondansetron, diphenhydramine 25 mg at bedtime for sleep, metoprolol, and enoxaparin. Bladder scan 520 mL. He has not had a bowel movement in 4 days. Labs: sodium 132, glucose 148, BUN 28, creatinine 1.1, WBC 11.2. The nurse requests an antipsychotic and restraints.
1. What is the most likely diagnosis, and what features support it over worsening dementia or a primary psychiatric cause?
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The most likely diagnosis is delirium superimposed on possible mild cognitive impairment, not a primary dementia syndrome or psychiatric illness.
Supporting features:
- Acute onset over hours to a day and fluctuating attention are cardinal delirium features.
- Disorientation and failure to recognize his daughter are new; before admission he managed finances and drove.
- Multiple reversible contributors are present: postoperative state, urinary retention (520 mL), constipation (4 days), pain, diphenhydramine, morphine, possible infection, and mild hyponatremia.
- Dementia alone does not typically begin abruptly postoperatively with fluctuating attention, though undiagnosed dementia can be a predisposing factor.
- Psychosis or mania would be less likely without prior psychiatric history and with this clear medical context.
The key reasoning is to treat delirium as a medical syndrome with multifactorial causes, not as “behavior” requiring sedation.
2. What nonpharmacologic and medical steps should be taken before considering an antipsychotic or restraints?
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Start with correcting contributors and supporting orientation.
- Remove the urinary catheter if no longer indicated and address retention; catheter-associated agitation and infection risk are common.
- Treat constipation with an appropriate bowel regimen; impaction can drive delirium.
- Optimize pain without oversedation: reassess morphine PCA use, consider scheduled acetaminophen and nonpharmacologic comfort, and avoid meperidine.
- Stop diphenhydramine; it is strongly anticholinergic and sedating in an older adult.
- Reorient with family presence, glasses, hearing aids, clocks, and daylight; maintain sleep-wake hygiene and mobilization with supervision.
- Work up reversible causes: repeat vitals, glucose, electrolytes, renal function, CBC, urinalysis only if urinary symptoms, chest imaging if hypoxia or cough, and review all medications.
- Use restraints only as a last resort for immediate danger, with the least restrictive device and frequent reassessment; restraints increase delirium, injury, and mortality.
Antipsychotics are reserved for severe agitation that threatens safety and has not responded to nonpharmacologic measures. If needed, use the lowest dose for the shortest time, avoid in Parkinson disease or suspected dementia with Lewy bodies, and monitor QT and sedation.
3. The daughter says, “He was fine yesterday; is this just dementia?” How do you explain the difference and plan follow-up?
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Explain that delirium is an acute disturbance of attention and awareness caused by a medical stressor, while dementia is a chronic, progressive cognitive decline. Delirium can occur in someone with mild memory problems, and the two can coexist.
Use plain language: “Your father’s brain is reacting to surgery, pain, poor sleep, a full bladder, constipation, and medications. This is different from a permanent dementia. It can improve when we fix those triggers, but it may take days to weeks.”
Plan:
- Track attention and orientation over time; document baseline cognition when possible.
- Continue nonpharmacologic measures and family involvement.
- Reassess after correcting retention, constipation, and diphenhydramine; expect fluctuation.
- Screen for depression and cognitive impairment after recovery, not during acute delirium.
- Explain that delirium increases future dementia risk and fall risk, so follow-up should include cognition, function, and medication review.
The reasoning: labeling acute confusion as “just dementia” risks missing sepsis, retention, medication toxicity, or hypoxia and can lead to inappropriate sedation.